Aim: 

The aim of the present work was to characterize phenotype differentiation of stem cells isolated from subcutaneous and visceral human adipocyte cells (S- and V-ASC).

Methods: 

Electrophysiological analysis by whole cell patch clamp, immunofluorescence, and real time RT-PCR analysis of the expression of stem cell markers.

Results: 

Muscular and neuronal differentiation was assessed by evaluating gene expression and protein levels of specific differentiation markers. The acquisition of the neuronal phenotype was confirmed by the occurrence of TTX-sensitive inward Na+ current. Moreover, records obtained from these cells bathed in TEA-Ca²⁺ plus TTX, showed Ca²⁺ currents arising from -20 mV due to L-type calcium channel activation, drastically reduced by nifedipine. ASC differentiated toward smooth muscular phenotype showed significant expression of the myogenic marker desmin. Electrophysiological experiments showed an inward transient current recorded from -30 mV with a time to peak of 25 ms. Starting from 0 mV it was followed by a slower decay suggesting the activation of high voltage activated L-type Ca²⁺ channels. Records made in the presence of nifedipine showed only the T-type Ca²⁺ currents.

Conclusions: 

Our data demonstrate that both visceral and subcutaneous adipose tissue are a source of resident pluripotent stem cells with multi-germline potential, thus representing a suitable in vitro model for experimental strategies of a stem cell transplantation therapy.